Adblock Plus
Removes LOADS of ads from the net by subscribing to a list of known ads. Also has the ‘open blockable items’ feature so you can scroll through every thing that is visible on that page and block it or right click and select ‘block this’. It even has tabs for flash and Java so you can block those ads too.
ADD IT HERE

Adblock Plus: Element Hiding Helper
Similar to that found in the Web Developer toolbar outline function, this allows you to mouse over a webpage and see the outline of the current element and then block it in Adblock Plus.
ADD IT HERE

Adblock Filterset.G Updater
Updates the filterset every 4-7 days.
ADD IT HERE

Foxmarks Bookmark Synchronizer
Allows you to save your Firefox bookmarks to a server and synchronize them up and down. Useful if you have more than one machine or are constantly re-formatting like me.
ADD IT HERE

Web Developer
An invaluable tool for any web developer out there regardless of ability. The tool I use the most is the ‘outline current element’ tool which draws a red line around the element the mouse is over and show the deprecation in the address bar. very helpful for understanding CSS problems.
ADD IT HERE

Google Preview
Shows preiews of pages next to the search result in google. Similar to that already done when YouTube videos appear in the search results. Uses the image taken from google’s webcrawler.
ADD IT HERE

del.icio.us
An integrated system for taging pages in your del.icio.us page. Comes with a menu bar as well as two menu buttons ‘tag this’ and a direct link to your del.icio.us page. Also feature right click integration.
ADD IT HERE

Feel free to list any other plugins that you use and why.

Its called ‘stylish’ and essentially overwrites the existing css of the page by using !important. So to remove ads its as easy as finding out the container’s name and setting it to display:none !important;. Easy right? Well actually it can be quite hard to find the names of what you want to change… thats why there is a dev community that has done it for you at http://userstyles.org/

All you do is install the ‘stylish’ add-on for firefox and then search the site for the pages that people have changed. So I searched for gmail and found hundreds of mods for it from simply removing ads to re-colouring the whole site. There are a few nice little applications that are web-wide (like the google ad blocking) and some that are only site wide (I have changed the colour of the Facebook header).

The great thing is, you can write your own or edit existing ones and preview all of them before saving them. Even then its a simple toggle-on, toggle-off system.

I recommend this for every web developer.

1. Open a new tab in firefox and type in about:config

2. In filter type pipe and you should have 3 results. Double click the top and the bottom to turn them to ‘true’ set the middle one to 20.

3. Right click anywhere on the list and select new > integer. Name it nglayout.initialpaint.delay and give it a value of 0. This sets the initial delay for showing web pages to zero.

4. Right click again anywhere on the list and select new > integer. Name it browser.cache.memory.capacity and give it a value of anything above 8,192. This is the memory that firefox will use in kb so I’ve set mine to 15000 but you can set it as high as you like.

Close and restart firefox and there you go! FASTERFOX!